That long description box describes everything that you NEED to have, not stuff you need to put yourself. This session file already has the set and all of its models for anyone to use. However, because it comes out of multiple universes, it is suggested that you use the content pack installer in SFM first.

If you get the Panda painting instead of the picture in the screenshot shown on the right, then you need to move the Portal assets above the workshop folder, or preferedly above stanleyparable.

Additionally, I have also provided direct links to the pages you need to subscribe to in order to obtain the item prerequisites and the map. Because it's not likely that subscribing to the session file will give you anything else.

Finally, there's plenty of tutorials on how to make animations and things with this.

Failure to follow directions written on description pages will result in ERROR models, missing textures and, at the worst bit, a "wrong map loaded" error.